1.Fruitless mulberry trees: roots break lawnmowers and these trees really pump out the allergenic pollen. Shade is also too deep for lawns.2.Sweetgum trees: big roots that poke out of the lawn.3.Pine trees: root problems and pollen too.4.Sycamore trees: usually grow way too large for most yards and they produce fuzz that makes people itch.5.Cedar trees: a female cedar is a nice, pollen-free tree, but grows way too large for most houses and yards.6. Magnolia trees: these have shallow roots and if you ever have to rototill your yard, if you have a magnolia tree in the lawn, you’ll be sorry. Shade is too dense too for most lawns.7.Lombardy poplars: these common trees grow fast and die young, leaving you with a huge mess. They also are male and produce lots of pollen.8.Olive trees: unless it is a Swan Hill or some other non-flowering olive, this one will cause all kinds of allergies. The olives are a big mess too.9.Walnut trees: nothing grows well under them and they produce lots of pollen and also smelly walnut fruit husks that draw flies.10. Brazilian Pepper trees: roots are a problem for mowing, the shade is too deep for lawns, and they cause skin rashes and other allergies.11. Seedless or fruitless Chinese Pistache trees: big producers of the most allergenic pollen. Slow to leaf out in spring.12. Catalpa trees: slow to leaf out in spring and fast to lose their leaves in the fall. No real fall color at all and they are known to shed considerable amounts of allergenic pollen each spring.

About the Author

Thomas Ogren is the author of Allergy-Free Gardening, Ten Speed Press. Tom does consulting work on for the USDA, county asthma coalitions, and the American Lung Associations. He has appeared on CBS, HGTV and The Discovery Channel. His book, Safe Sex in the Garden, was published 2003. In 2004 Time Warner Books published his latest: What the Experts May NOT Tell You About: Growing the Perfect Lawn. His website: www.allergyfree-gardening.com